docs: def generate_key(filtered_args):
      """Get a key from some input.
  
      This function should be used whenever a key is needed, to keep keys
      consistent.
      """
      # Convert the value to a (potentially singleton) tuple to be consistent
      # with joblib.filtered_args.
      if isinstance(filtered_args, Iterable):
          return hash(tuple(filtered_args))
      return hash((filtered_args,))